Mobile asphalt plant

ABSTRACT

A mobile asphalt plant, or the like, comprising: an elongated mobile chassis having a transverse vehicular passageway therethrough at one end; a drum-type mixer, for mixing aggregates and liquid asphalt, mounted on and extending longitudinally of the chassis, the mixer having inlet means, for the materials to be mixed therein, adjacent the other end of the chassis, and having an outlet adjacent the passageway; a holding bin carried by the chassis at the vehicular-passageway end thereof and movable vertically between a lower position within the passageway and an upper position above the passageway; means for raising and lowering the holding bin between its two positions; and an elevator pivotally mounted on the chassis for movement between a generally horizontal retracted position and an upright extended position, the elevator, when in its extended position, connecting the mixer outlet to the holding bin. The holding bin comprises a lower, downwardly convergent, frusto-conical portion and a cylindrical upper portion in telescopic relationship, such portions being relatively contracted for transport and relatively extended when the plant is in operation.

United States Patent Preeman Sept. 16, 1975 l l MOBILE ASPHALT PLANT[57] ABSTRACT lnvemori Marvin Preeman, L05 Angel, A mobile asphaltplant, or the like, comprising: an

Calif. elongated mobile chassis having a transverse vehicular [73]Assignec: Stansteel Corporation, Los Angeles, passageway thfirpethroughat one end; drum'type Calif mixer, for mixing aggregates and liquidasphalt,

mounted on and extending longitudinally of the chas- Filedi 1974 sis,the mixer having inlet means, for the materials to 21 1 Appl 498,593 bemixed therein, adjacent the other end of the chassis, and having anoutlet adjacent the passageway; a

holding bin carried by the chassis at the vehicular- U.S. passageway endthereof and movable vertically be- [51] Int. Cl. 328C 1/22 tween 3 l werosition within the passageway and an [58] Field of Search l. 259/ 159 R,I59 A, 157, upper ition above the passageway; means f i 259/158, 160,1655 i 176, 177 ing and lowering the holding bin between its two posi-177 A tions; and an elevator pivotally mounted on the chassis formovement between a generally horizontal rel l References Cited tractedposition and an upright extended position, the

UNITED STATES PATENTS elevator, when in its extended position,connecting the 2,805,052 9/1957 Prceman 259/159 A mixer outlet to theholding The holding bin 3,U7U 358 l2/l962 Heise 259/159 R prises alower, downwardly convergent, frusto-conical 3,116,051 12/1963Prccman... 259/159 R portion and a cylindrical upper portion intelescopic .611031 1 1/1 Paris 259/]77 R relationship, such portionsbeing relatively contracted for transport and relatively extended whenthe plant is in operation.

1 Claim, 4 Drawing Figures PATENTED SE-P I 6 I975 I SHEET 1 BF 2PATENTED l 6 3, 905,587

SHEET 2 BF 2 MOBILE ASPHALT PLANT BACKGROUND OF INVENTION The presentinvention relates in general to mobile mixing plants-and, moreparticularly, to a mobile asphalt plant similar to those disclosed in myearlier US. Pat. Nos. 2,805,052 and 3,116,051, respectively issued Sept.3,1957 and Dec. 31, 1963. Attention is also directed to the referencescited against my earlier patents.

As further background, a mobile asphalt plant of the type disclosed inmy prior patents comprises: an elongated mobile chassis having atransverse vehicular passageway therethrough at one end; a drumtypeaggregate mixer and dryer mounted on and extending longi tudinally ofthe chassis, the mixer having inlet means for the aggregates to be mixedand dried adjacent the other end of the chassis, and having an outletadjacent the passageway; a vertically movable structure carried by thechassis adjacent the vehicularpassageway end thereof and movablevertically between a lower position within the passageway and an upper,operating position above the passageway; means for raising and'loweringthe vertically movable structure between its two positions; an elevatorpivotally mounted on the chassis for movement between a generallyhorizontal retracted position and an upright extended position, theelevator, when in its extended position, connecting the mixer and dryeroutlet to the vertically movable structure; and the vertically movablestructure being provided with means for mixing liquid asphalt with theheated and dried aggregate mix emanating from the drum-type mixer anddryer.

OBJECTS AND SUMMARY OF INVENTION A general object of the invention is toprovide a mobile asphalt plant which is an improvement on those of myprior patents and outlined in the preceding section of thisspecification.

More particularly, an important object of the invention is to utilizethe drum-type mixer as a means for mixing the aggregates and the liquidasphalt, instead of doing this in the vertically movable structure, andto utilize the vertically movable structure as a holding bin for theresulting asphalt mix so as to provide an asphalt mix reserve permittingthe loading of a truck, or the like, in the vehicular passageway morerapidly, or to permit loading a number of trucks in rapid sequence. Withthe mobile asphalt plants of my prior patents, a truck could be loadedwith asphalt mix only as rapidly as such mix could be produced by therelatively small mixing section carried by the vertically movablestructure, which incurred undesirable delays.

The invention may be summarized as including, and an important object isto provide a mobile asphalt plant which includes: an elongated mobilechassis having a transverse vehicular passageway therethrough at oneend; a drum-type mixer, for mixing aggregates and liquid asphalt,mounted on and extending longitudinally of the chassis, the mixer havinginlet means, for the materials to be mixed therein, adjacent the otherend of the chassis, and having an outlet adjacent the vehicularpassageway; a holding bin carried by the chassis adjacent the vehicularpassageway end thereof and movable vertically between a lower positionwithin the passageway for transport and an upper position above thepassageway during normal operation; means for raising and lowering theholding bin between its two positions; and an elevator pivotally mountedon the chassis for movement between a generally horizontal retractedposition and an upright extended position, the elevator, when in itsextended position, connecting the mixer outlet to the holding bin.

The invention may be further summarized as including, and anotherimportant object is to provide a mobile asphalt plant wherein theholding bin includes, a lower, downwardly convergent, frusto-conicalportion and a cylindrical upper portion in telescopic relationship, theupper portion being telescoped downwardly over the lower portion whenthe holding bin is in its lower, retracted position, and the upperportion being extended upwardly relative to the lower portion when theholding bin is in its upper, operating position, the mobile asphaltplant further including means for moving the upper portion of theholding bin upwardly and downwardly relative to the lower portionthereof.

The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults thereof which will be evident to those skilled in the mobileasphalt plant art in the light of this disclosure, may be achieved withthe exemplary embodiment of the invention illustrated in theaccompanying drawings and described in detail hereinafter.

DESCRIPTION OF DRAWINGS FIG. 1 is a side elevational view of the mobileasphalt plant-of the invention in transport condition;

FIG. 2 is a top plan view of the mobile asphalt plant in its operatingcondition;

FIG. 3 is a side elevational view of a mobile aggregate storage unit foruse with the mobile asphalt plant; and

FIG. 4 is a side elevational view of the mobile asphalt plant in itsoperating condition.

DESCRIPTION OF EXEMPLARY EMBODIMENT OF INVENTION The mobile asphaltplant of the invention is designated generally by the numeral 10 andincludes an elongated mobile, vehicular chassis 12 of any suitableconstruction. For example, the chassis 12 may be equipped with trailerwheels l4and a hitch 16 for connection to a tractor, not shown, suchtractor elevating the adjacent end of the chassis 12 above ground levelfor transport. When the plant 10 is in its operating condition, as shownin FIG. 4, its weight is carried by suitable supports 18.

The chassis 12 is provided adjacent one end thereof with a transversevehicular passageway 20 of a size to permit the passage therethrough ofa truck,-or truck and trailer combination, not shown, to be loaded withasphalt mix. The passageway 20 is formed by an open rectangular frame 22having four legs 24 resting on four of the supports 18 in the operatingcondition. The open rectangular frame 22 provides a vertical passageway26 for a purpose to be described.

A drum-type mixer 28, for mixing aggregates and liquid asphalt, isrotatably mounted on and extends longitudinally of the chassis 12adjacent the frame 22. The mixer 28 is mounted for rotation and isdriven in conventional ways which need not be described.

The mixer 28, which slopes downwardly from its inlet end toward itsoutlet end, is provided adjacent its inlet end with inlet means 30 foran aggregate or aggregates and for liquid asphalt. More particularly,the inlet means 30 includes an aggregate inlet 32 which is supplied by aconveyor 34. As shown in FIG. 3, the conveyor 34, in turn, is suppliedwith an aggregate or aggregates by a conveyor 36 located belowindividual conveyors 38. These individual conveyors are respectivelylocated below aggregate bins 40 respectively containing different gradesof aggregate. The conveyors 36 and 38 and the bins 40 are carried by aseparate elongated mobile chassis 42 which may be transported to thedesired site independently of the chassis 12. The conveyor 34 fortransferring an aggregate or aggregates from the chassis 42 to theaggregate inlet 32 may also be separately transported.

Heated, liquid asphalt is delivered to the mixer 28 from a suitablesource, not shown, through an asphalt inlet pipe 44 extending into theinlet end of the drumtype mixer 28. This pipe is preferably flexible andcan be adjusted longitudinally of the mixer 28, depending on thecharacteristics of the mix. A burner 46 also directed into the inlet endof the drum-type mixer 28 serves to heat the materials delivered intothe mixer during the mixing process.

The hot asphalt mix produced in the drum-type mixer 28 is dischargedthrough an outlet into a fixed lower portion 48 of an elevator 50 havingan upper portion 52 hinged to the lower portion at 54. As will be seenby comparing FIGS. 1 and 4, the hinged upper portion 52 of the elevator50 is pivotable between a generally horizo'ntal retracted position,wherein it rests on supports 56, and an upright extended position. Whenthe mobile asphalt plant is in its operating condition, as shown in FIG.4, the elevator discharges the hot asphalt mix, through a dischargespout 58, into a holding bin 60 of the invention. The holding bin 60 isvertically movable between an upper, extended or erected position, shownin FIG. 4, and a lower, retracted position, shown in FIG. 1.,In itslower, retracted position, the holding bin 60 is disposed substantiallyentirely within the transverse vehicular passageway 20. In movingbetween its extended and retracted positions, the holding bin 60 movesvertically through the vertical passageway 26. I The holding bin 60 ismounted on a base 62 which is raised and lowered, to elevate and retractthe holding bin, by a suitable raising and lowering means 64. Thisraising and lowering means may be similar to those disclosed in detailin my aforementioned earlier patents so that no further'descriptionherein is required.

The holding bin 60 comprises a lower, downwardly convergent,frusto-conical portion 66 mounted on the base 62 and a cylindrical upperportion 68 telescopically related to the lower portion. Moreparticularly, when the holding bin 60 is in its lower, retractedposition the upper portion 68 thereof is telescoped downwardly over thelower portion 66 to reduce the over-all height of the mobile asphaltplant 10 for transport. However, when the holding bin 60 is in itsupper, operating position, the upper protion portion of the holding binis extended upwardly relative to the lower portion 66 thereof to obtaina large volumetric storage capacity for the hot asphalt mix, sufficientto load one or more trucks or truck and trailer combinations, forexample.

Thus, the holding bin' acts, in effect, as a surge chamber.

The lower and upper portions 66 and 68 of the holding bin 60 areinterconnected by telescoping struts 70, the two parts of each strutrespectively being connected to the base 62 and the upper portion 68 ofthe holding bin. The upper portion 68 of the holding bin may be raisedand lowered relative to the lower portion 66 thereof by air cylinders,hydraulic rams, or the like, not shown, incorporated in the struts 70.

It is thought that the over-all operation of the invention will be clearfrom the foregoing description so that a further explanation is notrequired.

Although an exemplary embodiment of the invention has been disclosed forillustrative purposes, it will be understood that various changes,modifications and substitutions may be incorporated in this embodimentwithout departing from the invention as hereinafter claimed.

I claim: 1

1. In a mobile asphalt plant, or the like, the combination of:

a. an elongated mobile chassis having a transverse vehicular passagewaytherethrough at one end;

a drum-type mixer, for mixing aggregates and liquid asphalt, mounted onand extending longitudinally of said chassis, said mixer having inletmeans, for the materials to be mixed therein, adjacent the other end ofsaid chassis, and having an outlet adjacent said passageway;

c. a holding bin carried by said chassis at said one end thereof andmovable vertically between a lower position within said passageway andan upper position above said passageway;

d. means for raising and lowering said holding bin between its saidupper and lower positions;

e. said holding bin including a lower, downwardly convergent,frusto-conical portion and a cylindrical upper portion in telescopicrelationship, said upper portion being telescoped downwardly over saidlower portion when said holding bin is in its said lower position, andsaid upper portion being extended upwardly relative to said lowerportion when said holding bin is in its said upper position;

f. means for moving said upper portion of said holding bin upwardly anddownwardly relative to said lower portion thereof; and

g. an elevator pivotally mounted on said chassis for movement between agenerally horizontal retracted position and an upright extendedposition, and said elevator, when in its said extended position,connecting said mixer outlet to said holding bin.

1. In a mobile asphalt plant, or the like, the combination of: a. anelongated mobile chassis having a transverse vehicular passagewaytherethrough at one end; a drum-type mixer, for mixing aggregates andliquid asphalt, mounted on and extending longitudinally of said chassis,said mixer having inlet means, for the materials to be mixed therein,adjacent the other end of said chassis, and having an outlet adjacentsaid passageway; c. a holding bin carried by said chassis at said oneend thereof and movable vertically between a lower position within saidpassageway and an upper position above said passageway; d. means forraising and lowering said holding bin between its said upper and lowerpositions; e. said holding bin including a lower, downwardly convergent,frusto-conical portion and a cylindrical upper portion in telescopicrelationship, said upper portion being telescoped downwardly over saidlower portion when said holding bin is in its said lower position, andsaid upper portion being extended upwardly relative to said lowerportion when said holding bin is in its said upper position; f. meansfor moving said upper portion of said holding bin upwardly anddownwardly relative to said lower portion thereof; and g. an elevatorpivotally mounted on said chassis for movement between a generallyhorizontal retracted position and an upright extended position, and saidelevator, when in its said extended position, connecting said mixeroutlet to said holding bin.